4.8. Transmission Electron Microscopy (TEM)

Transmission electron microscopy analysis of the isolated fractions was conducted as previously described [30]. Briefly, carbon-coated copper grids were glow-discharged to make the film hydrophilic (Pellco Easiglow, 0.2 mpar, 30 mA, 40 s, negative); then, ten microliters of F1–4 were applied to the grid and allowed to sit for 30 s. After removing the excess samples with filter paper, the grids were washed with distilled deionized water (ddH₂O) twice, followed by staining with 0.7% uranyl formate solution for 20 s. The grids were allowed to air dry before viewed. TEI Tecnai12 BioTwinG 2 electron microscope was employed to view the samples, and an AMT XR-60 CCD digital camera system was used to capture the samples. Experiment was repeated three times. At least two images from each repeat were used in the particle size determination using ImageJ (NIH, Bethesda, MD, USA).